My 2008 Ford Ranger Wildtrak (Manual transmission, 4x4, 2.5 TDCI) has been making two different weird noises lately according to below.
Sometimes when I take off from a stand still, a whining noise occurs from under the hood for a couple of seconds and then stops suddenly when I get up to reasonable speed. This has been occurring sporadically for about three months. I read somewhere that this could be due to a bad/loose fan belt, is that a reasonable explanation?
The second type of noise is more a kind of hard vibrating sound that appears to be coming from under the hood on the right side. I can describe the scenario. When I start the car, the vibrating noise starts in a pulsating manner with increasing frequency and the motor RPM increases simultaneously until it suddenly stops after about 5 seconds. To simplify, I start the car -> noise appears and motor RPM starts to go up br----------br---------br-------br-----br----br---br--br--br-br-br-br-br-br -> noise suddenly stops and motor RPM goes back to normal idling level. I first experienced this about two weeks ago and it have occurred maybe 5-6 times after that.
Other than these two things, the car runs perfectly fine. Are these issues likely to be correlated or separate? All kinds of help are greatly appreciated.